JP4787774B2 - Seal member and pipe joint - Google Patents

Description

  The present invention relates to a pipe joint for connecting the pipes by an inner cylinder fitted on the inner diameter side of the pipe to be connected, a seal member used between the pipe and the inner cylinder, and a pipe provided with the seal member Related to fittings.

  Conventionally, pipes made of synthetic resin such as cross-linked polyethylene and polybutene have been adopted as water pipes for water supply or hot water supply, and such pipes can be easily connected to each other or to devices such as headers (water separators). Various pipe joints have been proposed for reliable connection.

  Some of these pipe joints use an inner cylinder fitted on the inner diameter side of the pipe, and the seal member used between the inner cylinder of such a pipe joint and the pipe to be connected is made of a softer material than the pipe. It is manufactured, and is strongly pressed against the inner surface of the tube to be deformed to ensure a sealing property.

  Therefore, when the pipe is fitted, the seal member may be deformed and move in the fitting direction at the same time, and may protrude from the annular groove that accommodates the seal member, and how to eliminate the protrusion is a problem to be solved. It was.

  This problem has occurred more prominently when the pipe end cut surface is slanted, because a part of the seal member is not pressed from the inner surface of the pipe so that it tends to protrude.

  As what solves the problem, what was described in patent document 1 is proposed, for example, FIG. 6 is a figure which shows the principal part of the sealing member and inner cylinder of the pipe joint described in the patent document 1 It is.

  The pipe joint 40 includes an inner cylinder 32 fitted on the inner diameter side of a pipe to be connected, and a seal member 33 used between the pipe and the inner cylinder 32. The seal member 33 includes a protruding portion. 33a, a flat portion 33b, and a recess 33c provided between the protruding portion 33a and the flat portion 33b.

  The inner cylinder 32 is provided with an annular groove 32e that accommodates the seal member 33.

  The sealing member 33 is characterized by a flat portion 33b among the above-described components. Prior to the projecting portion 33a, the flat portion 33b is accommodated in a portion deeper than the rearmost portion of the oblique end surface and receives pressure from the entire circumference of the tube, even if the tube end surface to be connected is oblique. The movement in the axial direction is restricted by being pressed against the groove 32e.

  Therefore, when the tube to be connected is further pushed in and the tube tries to get over the protruding portion 33a, the movement of the seal member 33 in the pushing direction is restricted, and the seal member 33 is less likely to protrude from the annular groove 32e. And Patent Document 1 (paragraph [0018] of the specification).

  However, in such a seal member 33, the slope of the protruding portion 33a is such that the diameter is simply expanded uniformly. There is no escape area, and when the tube passes through the flat portion 33b and hits the protruding portion 33a, the resistance increases, and it is considered that reducing this resistance is one method for solving the problem of the protrusion.

  At this time, there is a method of making the gradient of the protruding portion gentle. However, in this case, there is a problem that the length of the gradient portion in the axial direction becomes long and the entire length of the seal member becomes long.

Further, in Patent Document 1, the flat portion 33b tried to solve the problem of protrusion, including the case of an oblique pipe end cut surface. However, the axial length of the seal member 33 is limited to only the flat portion 33b. There was a problem of becoming longer.
JP 2003-42370 A (FIG. 2)

  The present invention is intended to solve the above-described problem, can reduce the resistance when fitting a pipe, and can be used for a pipe having an oblique pipe end cut surface without increasing the axial length, It aims at providing the sealing member and pipe joint which can suppress the protrusion of a member as much as possible.

  The seal member according to claim 1 is a seal member used between the pipe and the inner cylinder in a pipe joint for connecting the pipe by an inner cylinder fitted on the inner diameter side of the pipe to be connected, An annular protrusion closely contacting the entire inner circumference of the tube, and a plurality of guide protrusions for guiding the tube toward the annular protrusion while partially contacting the inner periphery of the tube, and between the plurality of guide protrusions Is characterized in that a space allowing deformation of the annular projection and the guide projection pressed by the inner surface of the tube is formed.

  The seal member according to claim 2 is dependent on claim 1, and has an outer diameter (outer diameter formed by a top portion of the guide protrusion distributed on the circumference) only on a side of the guide protrusion that first contacts the pipe. The outer diameter of the inner cylinder is substantially the same as or smaller than the outer diameter of the inner cylinder in a state in which the seal member is mounted on the inner cylinder, and the apparent outer diameter is increased toward the annular protrusion.

  A pipe joint according to a third aspect is characterized in that an inner groove is provided with an annular groove, and the annular groove is provided with the seal member according to the first or second aspect.

  The pipe joint according to claim 4 is dependent on claim 3, and the axial length of the annular groove is such that when the pipe is inserted into the annular protrusion, the diameter of the seal member is reduced to extend in the axial direction. In order to allow, it is characterized by being formed longer than the axial length of the seal member.

  According to a fifth aspect of the present invention, there is provided the pipe joint according to the third or fourth aspect, wherein the annular groove includes a movement restricting portion for restricting movement of the seal member in the pipe fitting direction.

  The sealing member according to claim 1, wherein the annular protrusion is in close contact with the entire inner circumference of the tube, and the plurality of guides guide the tube toward the annular protrusion while partially contacting the inner periphery of the tube. And a space allowing deformation of the annular protrusion pressed by the inner surface of the tube and the guide protrusion is formed between the plurality of guide protrusions. As a result, it is possible to cope with an oblique tube end cut surface tube without increasing the axial length, and to suppress the protrusion of the seal member as much as possible.

  According to the seal member of the second aspect, in addition to the effect of the first aspect, the outer diameter of the guide projection on the side of the guide projection that first contacts the pipe is the inner cylinder in a state where the seal member is mounted on the inner cylinder. Since the apparent outer diameter is increased toward the annular protrusion, it is possible to smoothly reach the annular protrusion after fitting the pipe.

  According to the pipe joint of the third aspect, since the inner cylinder is provided with the annular groove, and the annular groove is provided with the seal member according to the first or second aspect, the effect of the first or second aspect is exhibited as the pipe joint. To do.

  According to the pipe joint of the fourth aspect, in addition to the effect of the third aspect, the axial length of the annular groove is such that when the pipe is fitted to the annular projection, the diameter of the seal member is reduced to extend in the axial direction. Since the seal member is formed to be longer than the axial length of the seal member, the gap between the annular groove and the seal member becomes a refuge for the seal member to be deformed by being pressed by the pipe. The protrusion of the member from the annular groove can be prevented.

  According to the pipe joint of the fifth aspect, in addition to the effect of the third or fourth aspect, the annular groove includes a movement restricting portion that restricts the movement of the seal member in the pipe fitting direction, and the seal member is the annular groove. It can be better prevented from protruding.

  Hereinafter, embodiments (examples) of the present invention will be described with reference to the drawings.

  FIG. 1 shows an example of a sealing member of the present invention, where (a) is a side view thereof, (b) is a front view thereof, (c) is an AA longitudinal sectional view of (b), and (d) is ( c) is a BB cross-sectional view, (e) is a CC cross-sectional view of (c), and (f) is an external perspective view thereof.

  This seal member 23 is used between the pipe and the inner cylinder of a pipe joint for connecting the pipe by an inner cylinder fitted on the inner diameter side of the pipe to be connected, that is, an inner diameter seal type pipe joint, The overall shape is a ring.

  The outside of the shape of the longitudinal section including the center of the ring shape of the seal member 23 is a truncated cone shape, and the lower part of the trapezoid is arcuate and continues to the end face side. The inner side of the ring-shaped longitudinal section is a stepped hole having a small diameter on the small side of the outer trapezoid and a large diameter on the large side.

  The arcuate outer peripheral portion of the trapezoidal lower portion is in close contact with the entire inner periphery of the pipe to be connected, and is referred to as an annular protrusion 23a. A plurality of guide projections 23b for guiding the tube toward the annular projection 23a extend from the upper part (smaller side) of the trapezoid while partially contacting the inner periphery of the tube to be connected.

  Between the plurality of guide protrusions 23b, an annular protrusion 23a pressed by the inner surface of the tube and a deformation allowing space WA that allows deformation of the guide protrusion 23b are formed. Such a guide protrusion 23b and the annular protrusion 23a are formed. These are the characteristic points of the seal member 23, and the function and effect will be described in detail later with reference to FIG.

  The outer diameter DD formed by the tops of the plurality of guide projections 23b distributed on the circumference is referred to as the outer diameter DD, and only the guide protrusion 23b is referred to as the outer diameter DD. The side abutting on the inner cylinder 22 is substantially the same as or smaller than the outer diameter D5 of the inner cylinder 22 used by fitting the seal member 23 in a state where the seal member 23 is mounted on the inner cylinder 22 (see FIG. 3A). ).

  In addition, it is another feature of the seal member 23 that the apparent outer circumference DD of the guide protrusion 23b is gradually enlarged toward the annular protrusion 23a as shown in the drawing. The effects brought about by the shape of the guide protrusion 23b will be described later in detail with reference to FIG.

  The small diameter side of the inner diameter side stepped hole of the seal member 23 is referred to as a small diameter hole 23c, and the large diameter side is referred to as a large diameter hole 23d. The opening side of the large-diameter hole portion 23d (the side that is not a stepped portion to the small-diameter hole portion 23c) has an arc shape and continues to the end surface side, and this arc portion is referred to as an inner arc portion 23e. The inner diameter of the small diameter hole 23c is D1, and the inner diameter of the large diameter hole 23d is D2.

  From the above description, and in particular, from FIG. 1C, the relationship between the outer and inner portions of the seal member 23 is that the outer annular protrusion 23a and the inner portion of the guide protrusion 23b in the vicinity thereof are the large-diameter hole 23d. It can be seen that the inner side of the outer guide projection 23b on the side opposite to the annular projection 23a is a small diameter hole 23c.

  As a material of the seal member 23, a material having flexibility and elasticity and good moldability is preferable, but soft synthetic resin rubber, more preferably, ethylene propylene is employed. The seal member 23 made of such a material exhibits good sealing performance by being pressed against the inner surface of a tube made of a synthetic resin such as cross-linked polyethylene or polybuden to be connected.

  FIGS. 2A and 2B sequentially show a state in which a pipe to be connected is fitted into an example of a pipe joint having the seal member of FIG. 1, and FIG. 2A shows a state in which the tip of the inner surface of the pipe is in contact with the seal member. (B) is a DD cross-sectional view of (a), (c) is an enlarged view of the main part of (b), (d), (e) and (f) are the inner end of the tube of the seal member It is the longitudinal cross-sectional view of the state which reached | attained to cyclic | annular protrusion vicinity, the EE sectional drawing, and the principal part enlarged view.

  2 (g), (h), and (i) are longitudinal sectional views of the state where the inner surface tip of the tube has completely passed through the annular projection of the seal member, its FF sectional view, enlarged view of the main part, (j), ( k) and (l) are a longitudinal sectional view, a GG sectional view, and an enlarged view of a main part in a state where fluid is supplied to the pipe and fluid pressure is applied to the inner surface of the pipe after the fitting of the pipe is completed. . In addition, the same code | symbol is attached | subjected about the part same as the part already demonstrated from this, and duplication description is abbreviate | omitted.

  The pipe joint 30 described in FIG. 2 is connected by being fitted into the seal member 23 in FIG. 1, the inner cylinder 22 in which the seal member 23 is fitted into the annular groove 22 d, and the outer side of the inner cylinder 22. And a cylindrical member 11 covering the outside of the tube P.

  In FIG. 2, hereinafter, the seal member 23 fitted in the annular groove 22d of the inner cylinder 22 is made of a pipe P (made of synthetic resin such as cross-linked polyethylene or polybutene, and the pipe P is fitted into the pipe joint 30. In this case, although it does not deform itself, it has flexibility as a tube.) It explains how it is deformed by fitting, and the engagement between the seal member 23 and the annular groove 22d is shown in FIG. 3 will be described.

  2A to 2C show a state in which the pipe P is fitted to the outside of the inner tube 22 of the pipe joint 30 and the inner surface tip of the pipe P is in contact with the guide protrusion 23b of the seal member 23. FIG.

  In this state, the seal member 23 is still in contact with the inner surface of the pipe P at the top portion of the guide projection 23b, is not pressed from the pipe P, and is not deformed. In this state, in the sealing member 23 of the present invention, the annular protrusion 23a and the guide protrusion 23b pressed by the inner surface of the pipe P are deformed between the plurality of guide protrusions 23b as shown in FIG. An allowable deformation space WA exists between the pipe P and the seal member 23.

  2D to 2F show a state in which the tip of the inner surface of the pipe P has reached the vicinity of the annular protrusion 23a of the seal member 23. FIG.

  In this state, the guide protrusion 23b is in a natural state, and gently moves toward the annular protrusion 23a whose apparent outer diameter DD (see FIG. 1) is large enough to maintain the sealing performance with respect to the inner surface of the pipe P. Therefore, as the pipe P is fitted, the diameter of the pipe P is reduced by receiving a restraining force from the inner surface of the pipe P.

  At this time, since the seal member 23 has the deformation-permitted space WA between the plurality of guide protrusions 23b, the flexible guide protrusion 23b can be easily separated from the deformation-permitted space WA by the amount pressed from the outside. Deform in the direction to make it smaller. Therefore, the introduction resistance caused by the fitting of the pipe P can be reduced as compared with the case where there is no such deformation allowable space WA.

  Moreover, in the thing of patent document 1, although it corresponded to the diagonal pipe end cut surface by the flat part 33b without introduction resistance, in this sealing member 23, in the fitting side inclination part of the protrusion part 33a in patent document 1 Since the corresponding guide projection 23b portion can reduce the introduction resistance, the guide projection 23b portion can also serve as the flat portion 33b of Patent Document 1.

  That is, in the seal member 23 of the present invention, the presence of the guide protrusion 23b having a small introduction resistance can cope with an oblique pipe end cut surface without providing a flat portion. It is not necessary to lengthen the direction length.

  In addition, since the apparent outer diameter DD is gradually increased toward the annular protrusion 23a, the apparent diameter DD is gradually increased toward the annular protrusion 23a, so that the resistance due to the deformation of the guide protrusion 23b when the pipe P is fitted is made smoother and smoother. The fitting of the pipe P can be made smooth.

  2G to 2I show a state in which the tip of the inner surface of the pipe P has completely passed through the annular protrusion 23a of the seal member 23. FIG.

  In this state, the annular protrusion 23a is in close contact with the entire inner surface of the pipe P and exhibits a sealing property, and the annular protrusion 23a is pressed against the inner surface of the pipe P to be deformed. At the same time as filling the gap portion, the deformation allowable space WA is also filled.

  That is, when the pipe P is fitted, the deformed portion of the annular projection 23a on the protruding side of the seal member 23 is not only on the back side of the annular groove 22d on the protruding side, but on the guide protrusion 23b side on the non-extruding side. Therefore, the seal member 23 is prevented from protruding and coming out of the annular groove 22d.

  2 (j) to 2 (l) show a state where fluid is supplied to the pipe P and fluid pressure is applied to the inner surface of the pipe P after the fitting of the pipe P is completed.

  In this state, fluid pressure acts on the inner surface of the pipe P and the pipe P expands in diameter, but the outer diameter of the pipe P is constrained by the tubular member 11 in the portion accommodated in the joint 30, The diameter is not expanded to the above. Here, since the diameter of the inner surface of the pipe P is also enlarged, a gap is formed between the inner end of the inner cylinder 22 and the inner surface of the pipe P.

  However, the annular protrusion 23a portion of the seal member 23 is in a state where the outer side is in pressure contact with the tube P constrained by the cylindrical member 11 and sufficiently seals are secured. Compared to the case where the above does not work, the deformation allowable space WA that is not filled in the seal member 23 is somewhat larger.

  In this pipe joint 30, the cylindrical member 11 is incorporated so as to be rotatable with respect to the inner cylinder 22, and the pipe P is strongly pressed against the cylindrical member 11 by fluid pressure and sealed by the seal member 23. It is possible to rotate with the cylindrical member 11 while ensuring the property.

  At this time, even if the pipe P rotates, the inner cylinder 22 and the seal member 23 of the pipe joint 30 do not rotate. That is, relative rotation occurs between the seal member 23 and the inner surface of the pipe P, and even in that case, the sealing performance by the seal member 23 is ensured.

  Even when fluid pressure does not act, the fitted pipe P is rotatable with respect to the pipe joint 30.

  Thus, according to the seal member 23 and the pipe joint 30 using the seal member 23, the resistance at the time of fitting the pipe P can be reduced, and an inclined pipe end can be obtained without increasing the axial length. It is possible to deal with a pipe having a cut surface, and the effect that the protrusion of the seal member 23 can be suppressed as much as possible is exhibited.

  As can be understood from the description of the annular protrusion 23a and the guide protrusion 23b described above, the core of the inventive idea that the seal member 23 embodies is that the inclined portion on the side where the tube of the seal member comes into contact with the fitting is entirely The guide protrusions are not partially in contact with the inner surface of the pipe, but are partially in contact with each other, and a space is provided between the guide protrusions to allow deformation of the seal member restrained by the pipe.

  As a result, the seal member of the present invention exhibits the effects of reducing the introduction resistance, dealing with an oblique pipe end cut surface, shortening the axial length, and preventing the seal member from sticking out.

  Therefore, the shape of the deformation allowable space to be formed is not limited to that illustrated in FIG. 1 as long as it achieves the above object. For example, the guide protrusion may be spiral and the deformation-permissible space may be spiral.

  In addition, the guide protrusion does not necessarily have to have an apparent outer diameter that gradually increases. For example, in order to gradually increase the abutting area on the inner surface of the tube, the one that replaces the change in apparent outer diameter, or the portion that first abuts on the inner surface of the tube is inclined, and then Alternatively, the guide protrusion may be replaced with an area of contact with the inner surface of the tube.

  In addition, as in Patent Document 1, a flat portion only corresponding to the end portion of the oblique cutting tube is unnecessary, and therefore, the extent of the diameter expansion of the outer diameter of the guide projection, that is, the seal member is increased by the length. It is also possible to reduce the introduction resistance of the tube by relaxing the degree of inclination from the inner surface of the tube to the annular protrusion.

  3A is an enlarged vertical cross-sectional view of the main part of the pipe joint described in FIG. 2, FIG. 3B is an enlarged vertical cross-sectional view of the main part showing another example of the pipe joint provided with the seal member of FIG. ) Is an enlarged vertical sectional view of a main part showing an example of a pipe joint provided with another example of the seal member of the present invention.

  The annular groove 22d includes a small diameter groove portion 22a into which the small diameter hole portion 23c of the seal member 23 is fitted, a large diameter groove portion 22b into which the large diameter hole portion 23d is fitted, and a step portion from the small diameter groove portion 22a to the large diameter groove portion 22b. And a movement restricting step portion 22c.

  What is important here is that the axial length L2 of the annular groove 22d is smaller than the axial length L1 of the seal member 23, and the diameter of the seal member 23 is reduced when the tube is fitted to the annular protrusion 23a. When the seal member 23 is longer than the pipe P as shown in FIG. 3A and is not fitted, the annular protrusion 23a of the seal member 23 is allowed to extend in the axial direction. A certain gap is formed between the side and the annular groove 22d.

  The operational effects resulting from the relationship between the axial length L1 of the seal member 23 and the axial length L2 of the annular groove 22d have already been described with reference to FIG.

  Further, as described in FIG. 1, the outer diameter DD is only applied to the portion of the guide projection 23 b of the seal member 23 that first contacts the inner surface of the tube P when the tube P is inserted, and the seal member 23 is attached to the inner cylinder 22. Since the outer diameter D5 of the inner cylinder 22 is substantially the same, the guide projection 23b smoothly abuts the inner surface of the pipe P having the same inner diameter as the outer diameter D of the inner cylinder 22, The fitting can be made smooth.

  As can be understood from the above description, the apparent outer diameter DD may be smaller than the outer diameter D5 of the inner cylinder 22 in this portion, and the same effect is exhibited in that case.

  Another important point is the relationship between the diameter D3 of the small-diameter groove 22a of the annular groove 22d and the natural diameter D1 (see FIG. 1C) of the small-diameter hole 23c of the seal member 23 fitted therein, and The relationship between the diameter D4 of the large-diameter groove 22b and the natural diameter D2 of the large-diameter hole 23d fitted therein (see FIG. 1C).

  Specifically, between the diameter D3 of the small diameter groove portion 22a and the diameter D1 of the small diameter hole portion 23c, when the small diameter hole portion 23c is fitted into the small diameter groove portion 22a, the small diameter of the elastic seal member 23 is provided. The hole 23c has a relationship such that the diameter is increased from 10% to 30%, more preferably approximately 17.7%.

  If the diameter expansion rate of the small-diameter hole portion 23c is less than 10%, the effect of preventing slippage is not exhibited, and if it is greater than 30%, damage such as tearing may occur beyond the allowable range of the elongation rate of the seal member 23. There is sex.

  On the other hand, between the diameter D4 of the large-diameter groove 22b and the diameter D2 of the large-diameter hole 23d, when the large-diameter hole 23d is fitted into the large-diameter groove 22b, the elastic sealing member 23 The large-diameter hole portion 23d has a relationship such that the diameter of the large-diameter hole portion 23d is 0% or more and 10% or less, more preferably approximately 7.2%.

  If the expansion ratio of the large-diameter hole portion 23d is smaller than 0% (minus), a gap is generated, which is not appropriate. If it is larger than 10%, the tensile stress state of the annular protrusion 23a portion in a state where the pipe P is not fitted. Becomes excessive, and the deterioration of the material increases.

  That is, when the seal member 23 is fitted into the annular groove 22d, the small diameter hole portion 23c expands more greatly, and is pressed and restrained by a larger force from the small diameter groove portion 22a. On the other hand, the large-diameter hole 23d has a smaller diameter, and the annular protrusion 23a on the outside thereof has a smaller elastic strain.

  From this relationship, according to this pipe joint 30 in which the seal member 23 is fitted into the annular groove 22d, the seal member 23 is sufficiently firmly restrained by the small diameter groove portion 22a of the annular groove 22d on the small diameter hole portion 23c side. Thus, the movement of the seal member 23 in the pipe fitting direction (the direction from the guide protrusion 23b to the annular protrusion 23a; the direction from right to left in FIG. 3A) is restricted.

  In this movement restriction, the movement restriction step part 22c from the small diameter groove part 22a to the large diameter groove part 22b of the annular groove 22d also participates to restrict the seal member 23 from moving more firmly in the pipe fitting direction. Yes.

  That is, according to this pipe joint 30, in combination with the annular protrusion 23a described in FIG. 2 and the guide protrusion 23b that generates the deformation allowable space WA, the seal member 23 is inserted into the pipe by the movement restricting step portion 22c. Therefore, it is possible to more effectively prevent the seal member 23 from protruding from the annular groove 22g when fitting the pipe.

  On the other hand, since the annular protrusion 23a is in a state where the elastic strain is smaller, when it is pressed against the inner circumference of the tube to be fitted, it is deformed more flexibly and has a better sealing property. Can be secured.

  As described above, the relationship between the small diameter hole portion and the large diameter hole portion is most desirably 17.7% on the small diameter (guide protrusion) side and 7 on the large diameter (annular protrusion) side. Although it is .2%, in relation to the property of the raw material of the seal member 23, a preferable result is produced within the above-mentioned ranges.

  The pipe joint 30A in FIG. 3 (b) is more round than the pipe joint 30 in FIG. 3 (a) in the annular groove 22g from the small diameter groove portion 22a to the large diameter groove portion 22f. The point which becomes the movement control convex part 22e used as the processus | protrusion which has is different. The diameter of the large-diameter groove 22f is the same as that of the large-diameter groove 22b shown in FIG.

  The roundness of the movement restricting projection 22e acts to minimize damage to the seal member 23 while maintaining the following movement restricting effect.

  According to the pipe joint 30A provided with such an annular groove 22g, the movement restricting convex portion 22e further enters the seal member 23 side, and the seal member 23 tries to move in the fitting direction of the pipe. It can block firmly and can prevent more effectively the sticking out of the annular groove 22g of the sealing member 23 at the time of pipe fitting.

  Further, the diameter expansion rate of the seal member described above is the relative relationship between the diameter of the small diameter groove portion of the annular groove and the natural diameter of the small diameter hole portion of the seal member, and the diameter of the large diameter groove portion. Some are determined by the relative relationship with the natural diameter of the hole.

  Therefore, if this relative relationship is appropriately selected, it is possible to achieve the same expansion ratio relationship without changing the outer diameter of the small-diameter groove portion and the large-diameter groove portion on the annular groove side. Since the movement restricting step portion is eliminated, the movement restricting convex portion as in the pipe joint 30A is particularly effective.

  In addition, the above-described movement restriction step part or movement restriction convex part corresponds to the movement restriction part described in the claims.

  The pipe joint 30B in FIG. 3C is provided with a chamfered portion 22h on the inner diameter side of the annular groove 22d ′, compared to the pipe joint 30 in FIG. 3A, while the annular protrusion of the seal member 23A. A difference is that an inclined portion 23f and an upright portion 23g following the inclined portion 23f are provided corresponding to the chamfered portion 22h side of 22a.

  The relationship between the chamfered portion 22h of the annular groove 22d 'and the upright portion 23g of the seal member 23A is such that the chamfering depth H of the chamfered portion 22h matches the upper position of the upright portion 23g. Yes.

  As a result, when the tube is fitted, the seal member 23A is pressed and compressed, and the upright portion 23g abuts against the upright wall surface facing the annular groove 22d ', the annular protrusion 22a portion of the seal member 23A is more effective. The seal is improved by smooth deformation.

  On the other hand, the portion that is about to protrude from the annular groove 22d ′ fills the space formed by the chamfered portion 22h and the inclined portion 23f, and is less likely to protrude to other portions.

  That is, according to the pipe joint 30B having such a configuration, it is possible to more effectively prevent the seal member 23 from protruding when the pipe is fitted.

  FIG. 4 is an exploded perspective view showing an example of a pipe joint including two seal members of FIG.

  The pipe joints 30 to 30B described with reference to FIGS. 1 to 3 focus on the operational effects of the seal members 23 and 23A that are the core of the present invention, and are elements obtained by discarding other pipe joint elements. The pipe joint 30C to be described below functions as an actual product incorporating all necessary elements as pipe joints.

  This pipe joint 30C uses two seal members 23 of FIG. 1, and therefore has the same configuration as the inner cylinder 22 already described, but is provided in the axial direction for two seal members 23. An inner cylinder 22C provided with the annular groove 22d and a cylindrical member 11A corresponding to the inner cylinder 22C are provided.

  In addition, the pipe joint 30C is constructed by assembling the inner cylinder 22C on one end inner diameter side, and connecting the pipe joint 30C to a desired device (for example, a water diverter) by the other end. Two retaining rings 24 provided with a plurality of retaining claws 24a for preventing slipping out, and a guide member 25 that guides the distal end portion of the pipe P at the final abutting portion of the connected pipe P are provided.

  The pipe joint 30 </ b> C is also on the back side of the guide member 25, and a seal ring (O-ring) 26 that performs a fluid seal between the joint body 21 and the inner cylinder 22 </ b> C, and an axis between the two retaining rings 24. A spacer 27 is provided to maintain the directional distance.

  The pipe joint 30 </ b> C is connected to the inner cylinder 22 </ b> C of the joint main body 21 as a part installed outside the connected pipe P, and connects the above-described cylindrical member 11 </ b> A and the cylindrical member 11 </ b> A to the joint main body 21. And an engagement portion 12 having a pipe connection confirmation window 13.

  The engagement between the engagement portion 12 and the joint body 21 is such that the movement in the axial direction is mutually restricted but the mutual rotation is allowed. The cylindrical member 11 </ b> A and the engaging portion 12 are collectively referred to as an outer cylinder 10.

  The inner cylinder 22C is adjacent to the annular groove 22d on the back side, and in order to externally fit the retaining ring 24, the spacer 27, the retaining ring 24, and the guide member 25, and then a connecting shaft cylinder for connecting and integrating with the joint body 21. And a male screw portion 22j that is provided at the tip of the connecting shaft cylinder portion 22i and engages with the female screw portion 21a of the joint main body 21.

  FIGS. 5A and 5B sequentially show a state in which a pipe to be connected to the pipe joint of FIG. 4 is fitted, and FIG. 5A is a longitudinal sectional view of a state in which the inner surface tip of the pipe is in contact with the seal member. Is a longitudinal sectional view of the state where the inner surface tip of the tube has almost reached the annular protrusion of the seal member, (c) is a longitudinal sectional view of the state where the fitting of the tube has been completed, and (h) is the tube after the fitting of the tube is completed. It is a longitudinal cross-sectional view of the state in which fluid is supplied and fluid pressure is acting on the inner surface of the pipe.

  First, as shown in FIG. 5A, the components of the pipe joint 30C described in FIG. 4 are assembled. At this time, in the assembled state, the seal ring 26 is interposed between the outer diameter of the connecting shaft cylinder portion 22i of the inner cylinder 22C and the inner diameter of the joint body 21, and the joint body 21 and the guide member 25. Is maintained between the joint body 21 and the inner cylinder 22C in the fluid seal state.

  Here, when the pipe P is inserted into FIGS. 5A and 5B, as already described in FIGS. 2 and 3, the seal member 23 is formed by the annular protrusion 2a and the plurality of guide protrusions 2b. The resistance at the time of fitting the pipe P can be reduced, and it is possible to deal with an oblique pipe end cut surface pipe without increasing the length in the axial direction, and the protrusion of the seal member 23 can be suppressed as much as possible. Demonstrate the effect.

  Now, as can be seen from FIG. 5 (c), in this pipe joint 30C, in order to further improve the fluid sealing performance, the sealing member 23 is installed adjacent to two places in the axial direction. Exhibits better sealing performance.

  Similarly, the removal of the pipe P fitted at one end is better prevented by the retaining rings 24 installed at two locations in the axial direction.

  Further, as can be seen from FIG. 5 (c), the engagement portion 12 has a pipe connection confirmation window 13 that is further expanded toward the outer periphery, so that the pipe P can be properly positioned at a predetermined position by viewing this. You can check if it is inserted.

  In addition, the tube connection confirmation window 13 can be fitted with a human fingertip or the like to confirm whether or not the tube P is properly inserted up to the tube connection confirmation window 13 by touch. In other words, the pipe connection confirmation window 13 cannot be visually confirmed at night, when there is no lighting, or because of the installation location of the pipe joint 30C, but even when the fingertip can be fitted, the pipe P is properly Insertion can be confirmed.

  As shown in FIG. 5 (d), when fluid flows through the pipe P and fluid pressure acts, the annular protrusion 23a of the first seal member 23 may reach the fluid pressure, but beyond that, Since the fluid pressure does not reach, the seal member 23 on the inner side can better exhibit and maintain the fluid seal.

  In addition, since the fluid pressure does not act on the part of the retaining ring 24 because it is blocked by the seal member 23 and the inner diameter of the pipe P does not swell, the retaining effect can be exhibited and maintained better.

  Moreover, since the engaging part 12 is rotatable with respect to the joint main body 21, the cylindrical member 11A is rotatable with respect to the joint main body 21, and the connected pipe P is in a connected state. The cylindrical member 11A, that is, the outer cylinder 10 can be rotated together.

  Therefore, even if the connection of the pipe P is a connection that gives an unnecessary twist to the pipe P, it is possible to eliminate the twist while maintaining the sealing performance after the connection.

  Note that the sheath connector and the sheath device according to the present invention are not limited to the above-described embodiments, and various modifications and combinations are possible within the scope of the claims and the scope of the embodiments. is there.

  The seal member and pipe joint of the present invention are for an inner diameter seal type of a pipe made of a synthetic resin such as cross-linked polyethylene or polybutene, and can reduce the resistance when fitting the pipe and increase the axial length. Therefore, it can be applied to a pipe having an oblique pipe end cut surface, and can be used in industrial fields where it is required to suppress the protrusion of the seal member as much as possible.

An example of the sealing member of this invention is shown, (a) is the side view, (b) is the front view, (c) is AA longitudinal cross-sectional view of (b), (d) is BB of (c). Cross-sectional view, (e) is a CC cross-sectional view of (c), and (f) is an external perspective view thereof. FIG. 1 sequentially shows a state in which a pipe to be connected is fitted into an example of a pipe joint including the seal member of FIG. 1, (a) is a longitudinal sectional view of a state in which the inner surface tip of the pipe is in contact with the seal member; (B) is a DD cross-sectional view of (a), (c) is an enlarged view of the main part of (b), (d), (e), and (f) are the tips of the inner surface of the pipe to the vicinity of the annular protrusion of the seal member A vertical cross-sectional view in a state of being reached, an EE cross-sectional view thereof, an enlarged view of a main part, and (g), (h), and (i) are vertical cross-sectional views in a state in which the tip of the inner surface of the pipe has completely passed through the annular protrusion of the seal member FF sectional view, enlarged view of essential parts, (j), (k), (l) are states in which fluid is supplied to the tube and fluid pressure is applied to the inner surface of the tube after the fitting of the tube is completed , Vertical sectional view, GG sectional view, enlarged view (A) is an enlarged vertical cross-sectional view of the main part of the pipe joint described in FIG. 2, (b) is an enlarged vertical cross-sectional view of the main part showing another example of the pipe joint provided with the seal member of FIG. The principal part expansion longitudinal cross-sectional view which shows an example of the pipe joint provided with the other example of the sealing member of this invention The disassembled perspective view which shows an example of the pipe joint provided with two sealing members of FIG. FIG. 5 shows a state in which pipes to be connected to the pipe joint of FIG. 4 are inserted in order, wherein (a) is a longitudinal sectional view of a state where the inner surface tip of the pipe is in contact with the seal member, and (b) is an inner surface of the pipe. (C) is a longitudinal sectional view of a state where the fitting of the tube is completed, and (h) is a state where fluid is supplied to the tube after completion of the fitting of the tube. Longitudinal sectional view of fluid pressure acting on the inner surface of the tube The principal part longitudinal cross-sectional view which shows an example of the pipe joint used as the background art of this invention

Explanation of symbols

22-22C Inner cylinder 22d, 22g Annular groove 22c Movement restriction step part 22e Movement restriction convex part 23-23A Seal member 23a Annular protrusion 23b Guide protrusion 30-30C Pipe joint
DD Apparent outer diameter (of guide protrusion)
WA Deformable space
L1 Axial length of seal member
L2 Axial length of annular groove
P tube

Claims (5)

In a pipe joint for connecting the pipe by an inner cylinder fitted on the inner diameter side of the pipe to be connected, a seal member used between the pipe and the inner cylinder,
An annular protrusion that is in close contact with the entire inner periphery of the tube, and a plurality of guide protrusions that guide the tube toward the annular protrusion while partially contacting the inner periphery of the tube;
A sealing member characterized in that a space allowing deformation of the annular projection pressed by the inner surface of the tube and the guide projection is formed between the plurality of guide projections.   Only the side of the guide projection that first contacts the tube has an outer diameter (the outer diameter formed by the top of the guide projection distributed on the circumference) of the inner cylinder in a state where the seal member is mounted on the inner cylinder. The seal member according to claim 1, wherein the apparent outer diameter is approximately equal to or smaller than an outer diameter, and the apparent outer diameter is increased toward the annular protrusion.   An annular pipe is provided in the inner cylinder, and the annular groove is provided with the seal member according to claim 1 or 2.   The axial length of the annular groove is longer than the axial length of the seal member so as to allow the seal member to reduce the diameter and extend in the axial direction when the tube is fitted to the annular protrusion. The pipe joint according to claim 3, wherein   The pipe joint according to claim 3 or 4, wherein the annular groove includes a movement restricting portion that restricts movement of the seal member in the pipe fitting direction.

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